let activeEffect = null
function effect(fn) {
  const effectFn = () => {
    try {
      activeEffect = effectFn
      console.log('activeEffect==', activeEffect)
      return fn()
    } finally {
      activeEffect = null
    }
  }
  effectFn()
}
effect(() => {
  console.log('调用effect-1')
})
effect(() => {
  console.log('调用effect-2')
})

